| Full text | |
| Author(s): |
de Paula, W.
;
Frederico, T.
;
Salme, G.
Total Authors: 3
|
| Document type: | Journal article |
| Source: | EUROPEAN PHYSICAL JOURNAL C; v. 83, n. 10, p. 30-pg., 2023-10-31. |
| Abstract | |
The unpolarized twist-2 (leading) and twist-3 (subleading), T-even, transverse-momentum dependent quark distributions in the pion are evaluated for the first time by using the actual solution of a dynamical equation in Minkowski space. The adopted theoretical framework is based on the 4D homogeneous Bethe-Salpeter integral equation with an interaction kernel given by a one-gluon exchange, featuring an extended quark-gluon vertex. The masses of quark and gluon as well as the interaction-vertex scale have been chosen in a range suggested by lattice-QCD calculations, and calibrated to reproduce both pion mass and decay constant. The sum rules to be fulfilled by the transverse-momentum dependent distributions are carefully investigated, particularly the leading-twist one, that has to match the collinear parton distribution function, and hence can be scrutinized in terms of existing data as well as theoretical predictions. Noteworthy, the joint use of the Fock expansion of the pion state facilitates an in-depth analysis of the content of the pion Bethe-Salpeter amplitude, allowing to calculate the gluon contribution to the quark average longitudinal fraction, that results to be similar to 6%. The current analysis highlights the role of the gluon exchanges through quantitative analysis of collinear and transverse-momentum distributions, showing, e.g. for both leading and subleading-twists, an early departure from the widely adopted exponential fall-off, for |k(perpendicular to)|(2)>m(2), with the quark mass similar to Lambda(QCD). (AU) | |
| FAPESP's process: | 16/25143-7 - Relativistic two and three-body problems in Minkowski space in (2+1) and (3+1) dimensions |
| Grantee: | Emanuel Arthur Ydrefors |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |
| FAPESP's process: | 17/05660-0 - Theoretical studies of the structure and reactions of exotic nuclei and many-body systems |
| Grantee: | Brett Vern Carlson |
| Support Opportunities: | Research Projects - Thematic Grants |
| FAPESP's process: | 18/21758-2 - Relativistic few-body problems and antiproton reactions |
| Grantee: | Emanuel Arthur Ydrefors |
| Support Opportunities: | Scholarships abroad - Research Internship - Post-doctor |
| FAPESP's process: | 19/07767-1 - Nuclear reactions with weakly-bound or cluster-structured radioactive and stable nuclei |
| Grantee: | Leandro Romero Gasques |
| Support Opportunities: | Research Projects - Thematic Grants |